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Credit card rules can confuse at the pump

Dollar limits are designed to help prevent fraud.

CHARLOTTE, N.C. - So you're at the gas station filling up your vehicle, and without warning the gas pump shuts off.

What? The tank isn't full, and you know your credit card isn't over its limit.

"Using my Visa card, I commonly hit a limit and I would be standing there scratching my head," said Shawn Bloomfield of Allentown, Pa., who pumps premium gas into his SUV. "I would always assume it is the gas station setting a limit on how much gas I could purchase. It felt like a ration scenario."

As the price of gasoline continues to rise, rules to prevent credit card fraud at the nation's pumps are confusing consumers who just want a full tank of gas.

Caps on transaction amounts - or the total dollar amount of gas a customer can pump into their car - are limiting some drivers of gas-guzzling vehicles.

"When I go to the gas station, I now have to use two credit cards just for one tank of gas," said Paul Brisgone of Oxford, Pa. "Kind of defeats the convenience of pay-at-the-pump."

"When I can go 400 miles a day, it inconveniences me if I need a full tank of gas and can't get one," said Brisgone, whose Ford F-150 pickup has a 32-gallon tank.

Credit card companies say the policies, which aren't new, are designed to ensure that merchants and consumers are protected from fraudulent transactions that could occur at a gas pump.

When a customer uses a credit card at a cardholder-activated terminal, such as a gas pump, the transaction is authorized without knowing the final bill of sale.

Typically, consumers who use a credit card are not liable for any fraudulent purchases, and gas merchants are not liable, either.

But credit card companies have established a protective layer by setting caps on how much gas a consumer can pump at any one given time.

That means in the event of any fraud," the merchant is protected from bearing the cost of the fraudulent transaction," said MasterCard spokeswoman Joanne Trout.

"Yes, it's an inconvenience," said Bloomfield, who often reaches his $50 limit when filling up his Nissan Pathfinder. "I guess you could say it's a necessary inconvenience for more secure transactions."